End brush



Nov. 7, 1961 R. W. DOLAN END BRUSH Filed Jan. 29,

\ .li|IIIIIIIIIIIIIIIIIIIIIIIIIIIII! INVENTOR.

@afer a4 nom/v United States Patent 3,007,188 END BRUSH Robert W. Dolan, Baltimore, Md., assignor to Pittsburgh Plate Glass Company, Allegheny County, Pa., a corporation of Pennsylvania Filed Jan. 29, 1958, Ser. No. 711,845 2 Claims. (Cl. 15--180) This invention relates to power-driven brushes and it has particular relation to power-driven brushes of the socalled endor cup-brush type in which double-length bristles or till are provided to extend approximately coaxially of the brush.

I-t has heretofore been -disclosed to form so-called end brushes by securing double-ended or folded iill material in a cup-like element which is provided with a central stem projecting coaxially lfrom the bottom thereof and being adapted to be secured in a chuck upon the end of a driven mandrel whereby to rotate the brush about its central axis.

Such brushes are well adapted for brushing or buiiing of surfaces having cavities and depressions which are diicult of access by conventional power-driven brushes of the disc or wheel-type.

In the fabrication of end brushes, fully satisfactory modes of securing the till material in the cups and especially those of smaller sizes have not heretofore been obtained. Obviously, a satisfactory end brush should be inexpensive to produce, simple of construction and should be rugged and .adapted to withstand long usage Without loss of the iill material. Also, the rfill material should be well and uniformly compacte-d into a rtight bunch. Also, there should be no axial voids, that might leave too many filaments Without support by neighboring tilaments.

One of the more com-mon prior art constructions in the end or cup brush field and comprising a cup holding the fill material, the cup having a stem projecting from the bottom and providing means whereby the brush is rotated about its longitudinal axis, is illustrated in Benyak patent, 2,449,158. In this construction, the iill material extends coaXially through a substantially cylindrical ring and is then doubled back about the outside of the ring to form a tuft which is held in cup. A disadvantage of this construction resides in the fact that it is difficult adequately to compress the ll material within the ring because of the incompressibility of the ring itself. Furthermore, the fabrication of such construct-ion is comparatively complicated, because it requires preliminary threading of a bunch of till through the ring and bending back of the bunch about -the outside of the ring before the brush knot is inserted in the cup.

In accordance with the provi-sions of the present invention in its preferred form an end brush is formed in which the doubled till material is secured inplace within a cup by means of a simple bar-like pin disposed in the loops or bights of the fill material and extending across the cup with the ends thereof appropriately embedded in or other- Wise locked in the metal of the cup by the distorting of portions of the side walls of the latter.

For Ia better understanding of the invention, reference may be had to the accompanying drawing-s in which:

FIG. l is a side elevational view of one embodiment of the invention. i

FIG. 2 is a sectional view taken substantially upon the line Irl-II of FIG. 1.

FIG. 3 is an elevational view of a slightly modiiied form of the invention. Y

FlG. 4 is a sectional viewsubstantially upon the line llV-IV of FIG. 3.

FIG. 5 is an elevational view of a third embodiment of the invention.

3,@7,l88 Patented Nov. 7, 1961 FIG. 6 is a sectional view of the construction as shown in FIG. 5.

4In the form disclosed in FIGS. 1 and 2, a brush cup element 8 having a cavity 9 formed by side walls 10 and bottom 11 is provided with an integral stem 12 projecting coaxiaily from the bottom of the cup. The stern and the cup may be provided by molding, pressing, machining or other appropriate techniques. The cup may be of iron, aluminum or the like metal. The stem 12 is designed fo-r insertion in a chuck or other convenient gripping device upon a mandrel or spindle designed to rotate the brush about its central axis.

Fill material for the brush, as a single unitary bunch 13, may be of any appropriate iilamentary material, such as nylon, or Tampico or metal such as steel, brass, bronze or aluminum wire, appropriately `doubled to provide two lengths of iilarnent for each strand. The bight portions of the laments are looped as shown at 14 about a transverse, bar-like pin 15, which has the end portions thereof actually pressed into the metal of the -side wall of the cup to provide .burr portions 16. An appropriate method of embedding the end of the pin in the metal comprises the performance of a pressing operation slightly to indent the metal of the side Walls as indicated at 17 directly over the ends of the pin. The pin is locked in position solely by indentation or embedment in the metal of the cup. ln this operation, punches having concave or cupped points adapted to tit over the areas contiguous to the ends of the pin may be employed. The points of the punches may, for example, have the outline of the letter P. The counters or concave portions of the letters -iit over the ends of the pins so that when pressure is applied to the punches, areas of the metal of the cup element S around the ends of the pin are forced inwardly, as a pair of ring-like shoulders indicated at 17 in FIGS. l, 2 and 3, and forming cups for the ends of the pin, thu-s securely enclosing and positively locking the latter from movement in all directions. The metal immediately over the ends of the pin is supported by the latter and is left standing out slightly in relief as islands 17a in the depressions. Both ends of the pin may be secured simultaneously by use of two punches Working in opposition.

Obviously the points of the punches may have other shapes than the letter P. They may, for example, be circles, triangles, squares, or the l-ike.

It will be apparent that it is feasible to employ pins which are cut to a length substantially corresponding to the internal diameter of the cup. It is also quite feasible to employ pins which are slightly longer than the diameter. In order to insert the latter pins, the cups may be slightly compressed temporarily to impart an ovoid section thereto permitting the pins to be inserted in transverse position. When the pressure upon the side of the cups is released, they Will inherently tend to spring back, tightly to grip the ends of the pins. The gripping action may further be promoted by the application of compression upon the portions of the side Walls of the cup over the ends of the pins thus more deeply embedding the ends of the pins in the metal of the side Walls of the cup.

In forming the brushes, the cup` may be placed beneath a suitable bunch or bundle of fill material of appropriate length, approximately at the mid-portion thereof, the pins may then be pressed down across the center of the bunch to force the bight portions thereof down into the cup and simultaneously to position the transverse holding pin 15. The bight portions of all the iilanients of the ll material are Ithus folded .about the pin. Subsequently, the side wall of the cup may be pressed, in order thoroughly and completely to embed the ends of the pin in the met-al. After the brush has thus been assembled, it is often desirable further to compress and to compact the till material at ythe top of the cup by pressing, spinning or otherwise crimping the upper edges of the cup as indicated at 19 about the projecting portions of the bristles.

Often the projecting end portions of the till material tend to be uneven. For purposes of evening up such ends, it is usually preferable to subject them to a trimming operation as will be well understood by those skilled in the art. Such operation is not particularly part of the present invention and they need not be described in detail.

In the embodiment of the invention as disclosed in FIGS. 3 and 4 of the drawings, the brush comprises a cup 20 with a side wall 21, a bottom 22 and a stern portion 23 coaxially and integrally formed upon the bottorn of the cup. The cup may be of such metals as have already been described, or others.

In this embodiment of the invention, one or more peripheral grooves or corrugations are formed about the cup portion 21 at a level spaced from the bottom of the cup. As illustrated in the drawings two of these peripheral grooves (26 and 27) are shown. These grooves are provided by a spinning or pressing operation and it will be apparent that they are so formed that inner peripheral ridges (28 and 29) are produced within the inner perimeter of the cup. One of these grooves, 26, may, if desired, be formed to provide a limit to the downward movement of the pin 31 locking the ll material 32 within the cup. The ridge 29 above the pin assists in locking the ends of the pin from upward displacement from the true, horizontal position.

It will be apparent that the peripheral depression 26 may be formed initially and the till material 32 and the pin 31 may then be pushed into position in the cup. Subsequently, the peripheral corrugation 27 may be formed in order to provide a positive lock for the ends of the pin. `It is not precluded, however, to form both of the peripheral grooves 26 and 27 as an initial operation and then to effect insertion of the ll material and the pin. In the latter event it is desirable prelimin-arily to spring the metal of the lside wall of the cup to avoid contour, thus permitting the pin to be inserted so that the ends thereof are disposed between the ridges 28 and 29. It will be apparent that the ends of the pin 31 may be further locked by application of pressure over the metal of the cup and diametrically opposed points corresponding to the ends of the pin.

In the form of the invention show-n in FIGS. and 6, a cup 33 which is essentially the same as that shown in FIGS. 3 and 4, except that a single peripheral corruga- Y tion 34, is provided. This projects outwardly to provide an internal channel 3S in which the ends of pin 36 are engaged, thus locking them in place to hold the till material 37. To permit the insertion of a pin of suicient length to engage the channel 35, the side wall of the cup may preliminarily be pressed or squeezed to avoid section and then be allowed to spring back to grip the pin, when the latter is in place.

It will be appreciated that ridges 28, 29 and 34 need not necessarily extend around the entire perimeter of the cups. They may comprise two short opposed segments of the perimeter.

It will be apparent that in a cup brush or end brush as herein disclosed, the till material is looped as a single bunch around the cross pin. There is no inner ring element Within the cup. Therefore, the till material may uniformly be compacted substantially across the entire cross-section of the cup. There are no projections upwardly from the locking pin which would tend to form axial open spots in the `lill material. Accordingly, all portions of the till material are uniformly supported by contiguous portions, thus giving uniform 'brushing or butling action and obtaining maximum life of the brush units.

FIG. 7 of the drawings illustrates a cup brush in which the doubled till material, such as a spring wire is held in the cup by a pin having `a stem portion projecting downwardly from the bottom of the cup to provide means for securing the brush in a chuck or other holding device. In this embodiment of the invention, the cup 38 has a cylindrical side Wall 39, a bottom 40 with a central opening. The securing element for the ll material comprises a cross-pin portion 41, which is adapted to be disposed in the bight or loop portion of the till material 42. The pin is provided with a stem portion 43, which projects through the opening in the bottom of the cup and provides the stem which is secured in the chuck of the mandrel or spindle.

The assembly of this brush is similar to that of the brushes described in FIGS. l through 6 except that two bunches of till material one upon each side of the stem portion 43 are provided. The stem is then inserted through the hole in the bottom 40 and the cross portion is forced down into the cup to provide the loop in the fill material and to secure the latter in place. Subsequently, the side Walls of the cup, about their upper edges, are crimped as indicated at 44 and the brush is trimmed to even the ends of the till material. The stem 43 may be secured from displacement in from the opening in the bottom of the cup by spot welding, or by a staking operation performed, for example, by nicking the side of the stem contiguous to the bottom of the cup as indicated at 4S.

It is also permissible to provide the stem with screw threads adapted to receive a threaded clamping nut engaging the bottom of the cup.

If desired to form a pilot-type brush, the stem 43 may -be extended upwardly as indicated in dotted line at E, beyond the ends of the bristles to provide a lead element.

The forms of the invention as herein described are by Way of illustration. It will be apparent to those skilled in the art that numerous modifications may be made therein without departure from the spirit of the invention or the scope of the appended claims.

I claim:

1. An end type brush comprising a cup, double-ended ll material having bight portions thereof disposed in the cup, a transverse, bar-shaped holding pin disposed in the cup and having the ends thereof engaging the walls of the Vcup upon opposite sides thereof, the ends of the pin being secured in place by pressing the metal of the cup inwardly from the exterior of the wall thereof to provide ringshaped shoulders around opposite ends of the pin, extending inwardly and embedding the ends of the pin within the cup whereby positively to hold the pin from movement in all directions, the bight portions of all of the double-ended ll material being looped about the pin and being retained in the cup by the pin, and a stem projecting axially from the bottom of the cup and providing means for holding the cup in a chuck for rotation about its central axis.

2. The end type brush as defined in claim 1 wherein the stem is integrally formed with the bottom of the cup.

References Cited in the tile of this patent UNITED STATES PATENTS 1,049,341 Chandler Jan. 7, 1913 1,138,466 Fogarty May 4, 1915 1,370,343 Montgomery Mar. 1, 1921 2,449,158 Benyak Sept. 14, 1948 2,771,625 Peloquin Nov. 27, 1956 FOREIGN PATENTS 481,883 Italy June 13, 1953 591,887 Germany Jan. 29, 1934 771,017 France July 16, 1934 UNITED STATES PATENT oEEICE CILRTIIFICATE 0F CGRRECTION Patent Nm 3900"?188 November Z 196i Robert We Dolan the above numbered pat- It is hereby certified that error appears in s Patent should read as ent requiring correction and that the said Letter corrected below.

Column 21 line 2Sl after "'FIG., 5J" insert the following as a new paragraphs FIGo 7 is a sectional View of still another type of brush Construction.,

Colulmnu lines 39 and 55 for "aVoidH each oocurrenoe read ovoi Signed and sealed this 23rd day of October 1962L1 (SEAL) Attest:

DAVID L. LADD ERNEST W., SWIDER Commissioner of Patents ttesting Officer 

